🍶 Rolling bottles and water: the whole packet

🍶 Rolling bottles and water · 5th–8th grade · 1 day of testing · free · 45 minutes a sitting

My days, if the fair is 14 days away

Count back from your fair day and write in each date. Fewer days than this? The jobs share days, in this order; nothing is skipped.

Dates from my teacher

• My question is due
• Testing starts
• My results table and graph are due
• My board is due

In this packet

1. 🗓️ My project plan
2. 💭 My hypothesis
3. 🧺 Change, measure, keep the same
4. 🪜 My steps
5. 📊 My results
6. 📓 My logbook
7. ✅ My conclusion
8. ✂️ Board titles to cut out
9. 🏅 The judge's questions and my certificate

If I change how much water is in the bottle, then how long the bottle takes to roll down the ramp will ________________, because _____________________________________________

What I think will happen, in my own words:

4 levels × 5 tries at each = 20 tries in all. If anything you keep the same changes, you won't know which change made the difference.

What I need

• 🧴 An empty plastic bottle: 1, with its cap
• 🚰 Water from the tap
• 📦 Flat cardboard: the longest flat piece you have, 60 cm or more
• 📚 Some books: 3, about the same thickness
• 🩹 Masking tape, to mark lines
• ⏱️ A stopwatch or a kitchen timer
• 🧽 A sponge or cloth, for wiping up
• 📏 A ruler

Be safe: 💧 Water · 🧽 A bit messy

1. Lean the cardboard on a stack of three books to make a ramp.
2. Stick masking tape across the top of the ramp as a start line, and across the bottom as a finish line.
3. Tape marks on the bottle a quarter and half of the way up, using the ruler.
4. Lay the empty bottle on its side on the start line, cap on tight, and let go. Don't push!
5. A helper starts the timer when you let go, and stops it when the bottle crosses the finish line.
6. Write the time in your table. If the bottle rolls off the side, don't count it: try again.
7. Do four more tries with the empty bottle.
8. Fill the bottle to the quarter mark, cap it tight, and do five rolls.
9. Add water to the half mark, cap it tight, and do five rolls.
10. Fill it to the top, cap it tight, and do five rolls.
11. Find the mean for each amount and draw a line graph.
12. Wipe up every spill when you are done.

Write each number in your results table the moment you measure it.

I changed: Water in the bottle   I measured: how long the bottle takes to roll down the ramp (seconds)

MY GRAPH (a line graph: water in the bottle along the bottom, seconds up the side)

What I noticed: ______________________________________________

Write something every day you work on it, even the days you only gather things. More days? The three-page logbook prints from peabody.kids/science-fair/templates/logbook.

My hypothesis was ☐ right ☐ partly right ☐ not right.

I know because my numbers show:

What surprised me, or what might have gone wrong (7th and up):

Next time I would test:

Idea: Change a second thing: run the same four amounts down a steeper ramp, and draw both lines on one graph.

1. What made you want to ask this question? Say something like: I wanted to know: does a full bottle roll down a ramp faster?
2. What did you think would happen, and why? Say something like: I thought changing how much water is in the bottle would change how long the bottle takes to roll down the ramp, and I wrote down why.
3. What did you change, and what did you measure? Say something like: I changed how much water is in the bottle (Empty, A quarter full, Half full, Full) and measured how long the bottle takes to roll down the ramp in seconds.
4. What did you keep the same, and why does that matter? Say something like: I kept the same bottle with its cap on tight and the same ramp at the same slope the same, so only how much water is in the bottle was different.
5. How many times did you test it? Say something like: 5 times at each of my 4 levels, and I found the middle number.
6. What did you find out? Show me in your numbers. Say something like: Look at my table: Empty and Full gave different numbers, and here's the pattern.
7. Was your hypothesis right? How do you know? Say something like: My numbers show whether I was right, partly right or not, and I can show you where.
8. Did anything go wrong, or surprise you? Say something like: One try was odd, so I did it again and wrote it in my logbook.
9. If you did it again, what would you change or test next? Say something like: I'd change a second thing: run the same four amounts down a steeper ramp, and draw both lines on one graph.